Respiratory devices



Oct. 1, 1963 A. M. RICHARDS RESPIRATORY DEVICES 3 Sheets-Sheet 1 Filed Sept. 17, 1959 INVENTOR; ALBERT M. RICHARDS.

ATTORNEY 3 Sheets-Shet 2 Filed Sept. 17, 1959 ALBERT M. RICHARDS.

Oct. 1, 1963 A. M. RICHARDS RESPIRATORY DEVICES Filed Sept. 17, 1959 s Sheets-Sheet s FIG. I2.

INVENTOR; ALBERT M. RICHARDS.

- structures usually employed for this purpose.

United Etates Patent 3,195,488 RESFLRATGRY DEVICES Albert M. Richards, 1356 Lowry Bldg, St. Paul, h iinn. Filed Sept. 17, 1959, Ser. No. $4 3,639 8 Claims. (Ql. l282) This invention relates to an improvement in respiratory devices and deals particularly with an apparatus which is portable and which may be used for forcing air and other gases into the lungs of a patient.

Various types of devices have been provided for supplying a patient with air, oxygen, or the like in order to produce positive pressure Ibreathing. Most such devices are similar to anaesthetizing apparatus and include tanks of various gases mounted on a Wheel hand truck or the like and which are too heavy and bulky to carry about from place to place. These devices include rubber portions which deteriorate with time, and must be replaced. Complicat-ed valves are employed for the control of the gas, and

these valves valve pistons must be inspecto periodically. Care must also be taken that the gas tanks are not empty or nearly depleted.

One of the primary purposes of the present invention resides in the provision of a portable unitary structure which is small in size and light in weight and which is readily portable, always available, and which requires little or no maintenance. The device is designed primarily for forcing air into the lungs of a patient to induce positive pressure breathing. Due to its low cost, small size, and light weight, it is practical for use in a much broader field than the heavy, expensive and complicated For example, the device may be readily used by life guards at public beaches or public swimming pools and other such points where the installation of most existing equipment used for this purpose would be impractical. The apparatus is also useful in locations where the use of oxygen and other inflammable gases cannot be safely used.

A feature of the present invention resides in the provision of a bellows type structure which may be expanded and contracted longitudinally. As the belows is manually expanded, air is drawn into the interior of the bellows. As the bellows is contracted, the air is forced through a Suitable valve apparatus into a mask which forms a part of the structure. This mask is designed to fit over tle nose and mouth of the patient in a manner usual to devices of this type. By contracting the bellows, positive pressure breathing may be induced.

A feature of the present invention resides in the provision of an apparatus of the type described having a mask formed in an end of the bellows so as to receive air directly therefrom. The valve means is interposed between the interior of the mask and the interior of the bellows to permit the patient to inhale and exhale in a normal manner without interference. At the same time, when the bellows is compressed, air is forced through the valve and into the mouth and nose of the patient.

A further feature of the present invention resides in the provision of an apparatus of the type described which may be used to supply a desired medicament in powder or vapor form to the patient. As an example, when a patient is stricken with certain types of heart and lung ailments, it is common practice to inject a strong dose of certain pharmaceutical preparations into the patient and to simultaneously apply artificial respiration or oxygen under pressure to produce positive pressure breathing. By quickly inserting a capsule of the desired preparation in the inlet of the mask, the pharmaceutical preparation may be supplied to the patient simultaneously with the air or oxygen under pressure to relieve the condition, particularly or where the hypodermic needle used to inject the preparation into the body of the patient is not available.

The present device is useful in emergencies when the lungs fill with blood or other fluid, or are so scarred and contracted as to be unable to move air. The apparatus is particularly useful for home use by patients having chronic lung ailments, due to its low cost, ready availability, and lack of need for maintenance. Normally, exhalation of air is an elastic recoil following inhalation, but in some instances it is impossible for the patient to inhale enough air to cause a reflex exhalation. By inducing positive pressure inhalation somewhat beyond normal inhalation pressure, the reflex exhalation will ensue.

A further feature of the present invention resides in the provision of a device of the type described which, in its collapsed form, is compact and requires little space for storage. In the preferred form, a shell is provided into which the bellows extend for protection of the bellows when the device is not in use.

A further feature of the present invention resides in the device of the type described which may :be used in conjunction with a supply of oxygen or other gas where desired. The interior of the bellows is provided with an inlet which may be connected to an oxygen tank or the like where such is available. By inserting oxygen into the bellows under low pressure, the bellows may be expanded or contracted to induce positive pressure breathing controlled by the action of the bellows.

A further feature of the present invention resides in the provision of a device of the type described which may include means for connecting the interior of the bellows with auxiliary masks or tracheotomy tubes where it is so desired. For example, when the device is used in an operating room or following special treatment such as a shock treatment or the like, under the supervision of a trained anaesthetist, this person in some instances will prefer to employ a mask of conventional form with which the anaesthetist is more familiar. In such an instance, an

adapter may be connected to the outlet of the bellows leading to a mask of conventional form or to an air way so that the apparatus may be used with such a mask or other attachment.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims:

In the drawings forming a part of the specification:

FIGURE 1 is a perspective view of the respiratory device showing the general arrangement of parts when the :bellows is in expanded form.

FIGURE 2 is a vie-w similar to FIGURE 1, showing the device in contracted form.

FIGURE 3 is an end elevational view of the apparatus, showing the handle end of the structure.

FIGURE 4- is an end 'elevational view showing the mask supporting end of the apparatus.

FIGURE 5 is a sectional view through the respiratory device in contracted form showing a valve arrangement which may be used in the construction.

FIGURE 6 is a sectional view through the value, the position of the section being indicated by the line 66 of FIGURE 5.

FIGURE 7 is a perspective view of a cartridge which may be used to supply a medicant to the patient.

FIGURE 8 is an enlarged sectional view through the capsule of FIGURE 7 when in place in the mask inlet.

FIGURE 9 is a sectional view through a portion of the mask and through a portion of an auxiliary mask attached thereto.

FIGURE 10 is an enlarged fragmentary sectional view of the flap valve portion of the device.

FIGURE 11 is an enlarged sectional elevation of a filter employed in the inlet end of the valves.

FIGURE 12 is an end view of a modified form of construction of respiratory device.

FIGURE 13 is a sectional view through the device, the position of the section being indicated by the line 13-43 of FIGURE 12.

FIGURE 14 is a sectional view taken on the line 14-14 of FIGURE 12.

The respiratory apparatus includes an expandable and contractable bellows which is connected at one end to a mask supporting end member 11 and which is connected at its other end to a handle supporting end member 12. Upon reciprocation of the end members 11 and 12, the bellows may be expanded or contracted to draw air into the bellows and to expel it into the mask in a manner which will be described.

The handle end member 12 is shown as comprising a disc like closure plate 13 having a generally U-shaped handle 14 connected thereto or forming an integral part thereof. The handle 14, in the form illustrated, includes .a cross member 15 connected at its ends by end connecting members 16 to the disc 13.

The bellows It is of flexible resilient material or of merely flexible material having its side walls 17 of corrugated form to permit the bellows to be expanded and contracted. One end of the side wall 17 includes a cylindrical sleeve portion 19 which frictionally or resiliently encircles the disc 12. A retaining ring 20 may encircle the cylindrical portion 19 to form a tight connection between the disc 12 and the end of the bellows.

The end member 11 is shown as including a generally cylindrical wall 21 which is connected at its outer end to a generally convex closure panel 22 having a concave center portion 23-. The convex and concave portions 22 and 23 are connected by the grooved portion 24 of generally heart shaped form as illustrated in FIGURE 4 of the drawings. The groove 24 is of proper shape and contoured to fit over the mouth and nose of a patient. In other Words, the base of the groove is not on a common plane and varies both in outline shape and in elevation to fit the general form of the face of a patient.

A ring 25 of compressible material such as foam rubber or the like follows the contour of the groove 24- and is held in place by suitable means such as by a rubber diaphragm 26 of generally ring-shaped form having it inner edge looped as indicated at 27 to encircle the ring 25. The peripheral edge 29 of the diaphragm 26 is stretched about the outer surface of the cylindrical portion 21 of the mask and may be resiliently held in place.

The cylindrical portion 21 is connected by an outwardly projecting off-set 30 to a generally cylindrical sleeve 31 be anchored therein to hold the device in its contracted form. With reference to FIGURES 1 and 2 of the drawings, it will be noted that one or more radially extending pins 32 may project from the outer surface of the ring 2e encircling the disc 13 and may extend into bayonet slots 33 in the outer end or open end of the sleeve 31. These slots 33 are provided with hook shaped ends 34 into which the pins 32 may be engaged by slightly rotating the end 12 relative to the end member 11, the bellows flexing sufiiciently to permit the pins 32, to engage in the ends 34 of the slots 33 in the manner illustrated in FIG- URE 2 of the drawings, to hold the end members connected in bellows in closing position.

A check valve is provided to permit the entrance of air into the bellows 10 as the bellows is expanded and to prevent the flow of air from the bellows through the check valve while the bellows is being compressed. This check valve is shown in the form of an aperture 35 extending through the closure plate 13 and in the provision of a resilient flap 36 of rubber or other suitablematerial which is anchored along one edge as indicatedat 37 and which merely acts as a closure for the aperture 35 when the bellows is being compressed. As the bellows is being expanded, the flap valve 36 may flex into the position illustrated in dotted outline in FIGURE 5 of the drawings to permit air to be drawn through the aperture 35. FIGURE 5 of the drawings illustrates the aperture 35 as being located centrally of the disc 13. However, in actual practice, the aperture 35 is preferably offset near one end of the handle 14 so that the opening cannot be covered by the hand in expanding and contracting the bellows.

A relief valve 39 is also provided and is illustrated as extending through the disc closure 13. The relief valve 39 includes a valve seat 40 and a valve element 41 arranged on the end of a plunger 42 and urged into closed positions by a spring 43. The relief valve 39 is designed to prevent the building up of a pressure within the bellows to an extent which would be injurious to the patient. Devices of the type in question are normally used in cases of emergency and may be used by persons inexperienced in the proper method of operation. The relief valve prevents injury to the patient during operation. In preferred form, the valve 39 includes a whistle element 44 which functions when actuated to provide an audible indication that the permissible pressure is being exceeded, suggesting airway obstruction.

In order that the mask portion of the device he held in proper position over the nose and mouth of the patient, a bracket is provided projecting from the bellows end 11. The bracket 45 includes a strip portion 46 which extends generally parallel to the axis of the bellows and which is curved to provide a rounded channel 47 designed to accommodate the thumb of the operator. The bracket also preferably includes an offset end portion 49 which is designed to extend over the back of the hand of the operator so as to provide a control of the device in use.

In the use of respiratory masks, it is common practice for the operator to hold the mask with a thumb and forefinger and to extend the other fingers about the chin of the patient so as to properly locate the mask relative to the nose and mouth. The clip on bracket which I have provided permits the mask to be held in place and properly located by the fingers of the operator.

Straps 45% secured to the end member 11 of the mask are designed to extend about the head of the patient to hold the mask in place.

The valve which controls the flow of air into and out of the mask is perhaps best illustrated in FIGURE 5 of the drawings. An opening 50 is provided through the concave portion 23 of the bellows end 11. The valve element is shown as including a sleeve 51 which extends snugly into the aperture 5% and is sealed relative thereto by means of a gasket 52 interposed between a portion of V the end member 11 and a peripheral flange 53 of the sleeve 51. In the particular arrangement illustrated, the sleeve 5-1 communicates with a conduit 54 leading to a valve chamber 55. The valve chamber 55 is provided with an aperture 56 extending therethrough and which is normally closed by a resilient flap valve 57 which is secured to the valve chamber along one edge 59 and which normally forms a closure to prevent air from passing from the valve chamber 55 to the interior of the bellows 1%. On the other hand, when the interior of the bellows is subjected to greater pressure than that existing in the valve chamber, the flap valve 57 will flex away from the opening 56 to provide a communication from the interior of the bellows It} to the conduit 54 so that air under pressure may be forced into the mask.

The valve chamber 55 is provided with a partition 69 including an outlet connection 61 which may also be sealed by the flap valve 57 when the pressure within the bellows exceeds that in the valve chamber 55. The partition 6t defines an outlet chamber 62 which communicates with a conduit 63 extending through the bellows end 11 and terminating in communication with atmosphere at the end 64. The portion of the valve chamber 55 encircling the aperture 56 is normally shaped to closely fit the resilient flap valve 57, and a wall 58 forms a seal with the end of flap valve 57 until the valve seats against the end or the outlet connection 61. Further bellows pressure acts to hex the end of the flap valve as shown in dotted outline in FIGURE 5, permitting the air from the bellows to enter the valve chamber 55.

When the operator is desirous of inducing positive pressure breathing in the patient, compressive pressure is applied to the bellows While the mask is held over the nose and mouth of the patient. As the air within the bellows 19 is compressed the flap valve 57 first seals the outlet connection 61 and then flexes inwardly until air is forced through the valve chamber 55 and the conduit 54- into the interior of the mask. However, at the end of the stroke, as bellows pressure is released and the bellows 10 is expanded, air enters the bellows past the flap valve 36. At the same time, the flap valve 57 returns to normal position closing the opening 56. The patient may then exhale or inhale normally, there being an open passage through the conduit 54, the valve chamber 55, the outlet passage 61, the chamber 62, and the outlet conduit 63 to outer atmosphere. During this time, the partial vacuum within the bellows as -well as the natural resilience of the flap valve will hold the flap valve 57 in sealing relation to the opening 56 to prevent the patient from exhaling into the interior of the bellows. In other words, air may be forced into the lungs of the patient under positive pressure, when the bellows is compressed, but under other conditions the interior of the mask is connected directly to the outer atmosphere.

A nipple 65 which is normally closed and in suitable means such as by a plug 66 extends through the bellows end 11. This nipple 65 is designed for connection with a tubular conduit 67 leading to a suitable source of supply of oxygen or the like. In other words, the bellows may be filled with oxygen or another gas which may be forced into the lungs of the patient by the bellows and positive pressure breathing may be induced using oxygen rather than air as the gas. Obviously, as soon as any pressure greater than atmosphere exists within the bellows, the flap valve 36 will spring into, and remain in, closed position.

FIGURES 7 and 8 of the drawings disclose a cartridge 69 which may be used to contain a medicament which may be directed into the lungs of the patient. The member 69 has a generally cylindrical outer surface 76 which defines two substantially semi-circular compartments 71 and 72 as indicated in FIGURE 8 of the drawings. The compartments 71 and 72. have a common circular bottom panel 73 and offset top panels 74- and 75, the compartments 71 being substantially longer than the compartment 72. The compartment 71 is designed to contain the medicament which is indicated in general by the numeral 76 and is provided with perforations 77 through which air may pass after being forced through the medicament. The chamber 71 also includes inlet passages 79 through which air may be forced by the bellows 10.

The top closure panel 81 of the compartment 72 is provided within an aperture 81. A resilient flap valve 82 is supported within the compartment and is designed to close the aperture 31 when the pressure within the bellows exceeds the pressure within the mask. An opening 83 is provided in the end wall 73 of the compartment 72 and provides a communication between the compartment 72 and the interior of the sleeve 50. The inner end of the capsule 69 is provided with bayonet slots 85 to accommodate pins 86 which detachably hold the capsule in place.

In operation, when it is desired to employ the medicament, the capsule 69 is inserted into the sleeve 58 and rotated to engage the pins 8-6 in the slots 85. As air is forced from the bellows 10, it passes through the inlet passages 79, through the medicament 76 in the medicament chamber '71, and through the opening 77 to th interior of the mask.

As the patient exhales, the pressure differential acts to open the flap valve 82 and to permit the air being exhaled to pass directly through the passage 8-9 and the passage 84 into the interior of the sleeve 5% from where it may pass to atmosphere in the manner previously described.

In FEGURE 9 of the drawings, 1 disclosed an auxiliary attachment which may be usedwith the mask. A sleeve 99 is provided which snugly fits into the sleeve 56. Bayonet slots 91 are provided to accommodate the pins 36 used to support the medicament capsule. A respiratory mask 92 of conventional form, an air way, or a tracheotomy tube is attached to the sleeve 9%) and may be used in place of the mask previously described.

The only difference between the construction shown in FIGURE 9 and the previously described construction lies in the provision of the extension which permits a better view of the face of the patient. Under normal operation, the built-in mask has been found to be preferable and it is accordingly more commonly used.

If desired, a filter may be employed to filter the air entering the bellows. A cartridge 94 filled in any way with filtering material 95 may be inserted in the inlet opening 35. The cartridge 94 may be held in place frictionally, threaded into place, or held by pins and bayonet slots such as have been used to hold the cartridge 69 in place. The filter may, if desired, be impregnated with an absorbent or adsorbent material. The filter may be composed of filter discs through which air may pass, or may be a material such as granulated activated charcoal or the like.

When the nipple 65 is connected to an oxygen supply, as described, there is a possibility that air will be admitted through the valve 36 as the bellows is expanded. Fi URE ll discloses a reduced diameter sleeve 93 on the cartridge 94 which may accommodate an oxygen supply tube. When used to supply oxygen, the filtering material may be removed.

A modified form of respiratory device is illustrated in FIGURES l2, l3 and 14 of the drawings. This device includes a bellows tea which is flexibly supported between a pair of end members 1%]. and 102. The end member 101 includes a concave-convex shell it?! having a concave central depression 163 which extends partially into the bellows 1%. An inwardly projecting flange 10a is provided on the inner surface of the shell 102 encircling the concave portion 1&3 and one end of the bellows 1% is interposed between the flange 194 and a sealing or attaching ring 195.

The end member 102 includes an end plate 1% and a curved encircling wall 197 which extends into edge abutting relation with the edge of the shell 192 to form a closure for the bellows ltli) in closed position of the structure. The end plate 166 is provided with a circular flange 169 projecting inwardly therefrom. The end oi the bellows lilil opposite that secured by the sealing ring 1&5 is interposed between the flange Hi9 and a sealing ring 11% which is held in place by clamping screws 111 or other suitable means. The bellows 1% is thus arranged to provide a connecting member between the end members ltll and E2 and may be expanded or contracted by relative movement between the end members.

A pair of parallel sleeves lllproject from the outer surface of the end plate 111 generally parallel to the axis of the bellows and acts to support a handle disc 113 having a convex outer surface which generally follows the curvature of the wall 187. As indicated in FIGURE 12 of the drawings, this handle disc 113 is provided with an irregular outline 114 which is shaped to permit the disc to be engaged between the fingers and thumb of the hand of an operator. This edge 114 is in spaced relation to the base plate 106 so that the handle disc may be readily grasped and held.

A plastic instrument known as an airway 113 may be frictionally engaged between the handle 113 and the end plate 136. This airway may be effectively used with the bellows, the tube fitting into the throat to provide an artificial air passage.

As is evident from FIGURES 13 and 14 of the drawings, the sleeves 112 are formed by two sleeve portions, one portion 115 being integral with the end plate 1% and the portions 116 being integral with the handle disc 113. A clamping plate 117 is provided inwardly of the end plate 1% and includes threaded sockets 119 into which the ends of a pair of clamping bolts 12% may extend. The clamping bolts 12% extend through the sleeves and hold the two portions of each sleeve assembled and also hold theclarnping plate 117 in place. A valve element 121' of resilient material has one of its ends clamped against the end plate run for a purpose which will be described.

As is indicated in FIGURE 13 of the drawings, a partition wall 122 connects the end .plate 196 with the disc ll?) and diverging walls 123, best illustrated in FIGURE 12 of the drawings, extend from the partition wall 122 to a point near the periphery of the disc 113. These walls 123 inclined together at a juncture with the end plate 1% and lead to an opening 124 in the periphery of the disc 113. The walls 122 and 123 are formed partially on the end plate 1% and partially on the disc 113 for simplicity of molding. A third sleeve 125 similar to the sleeves 112 extend between the end plate 1% and the disc 113 and a bolt or screw 126 extends through the portion of the sleeve attached to the disc 113 and is threaded into the portion of the sleeve attached to the end plate 166.

As indicated in FIGURE 13 of the drawings, the end plate tee is provided with an aperture 127 extending therethrough between the walls 123, this aperture 127 being normally closed by the resilient flap 121. This flap 21 normally closes the opening 127 but will flex inwardly as the bellows 1% is expanded to permit air to enter the bellows. The flap 121 will close the opening when the expanding action is discontinued and when the bellows is being compressed.

A pressure relief valve is mounted upon the end plate ill 5. The valve 129 is shown as including an end plate 13% having a sleeve 13 projecting from its inner surface. This sleeve 713i is slidable through an aperture 132 in the end plate 1%. A disc 133 is supported in spaced relation to the end plate 139 by an adjustment screw 134. A spring L35 is interposedrbetween the end plate 106 and the disc 233. Apertures such as 136 are provided in the sleeve 131' which are normally closed by the walls of the opening 132 but which are opened when the end plate moves away from the end plate 106.

in operation, the spring 135 holds the valve 129 normally closed. However, if the pressure Within the bellows exceeds a predetermined maximum which is safe to use within the bellows when applied as a mask, such as a pressure of perhaps 40 millimeters of mercury above atmospheric pressure, the air will act against the plate 136 to open the valve and to permit air to escape through the vent apertures 136.

In this arrangement, a pair of oppositely disposed arms 137 and 139 project in diametrically opposed relation from the end member 161 on opposite sides of the concave surface 1% to support the concave convex body 149 of the mask. As in the other forms of construction, a soft resilient gasket 141 encircles the periphery of the mask body 1 to form a seal against the irregular contour of the face. The arm 131) is shown as being hollow in form providing an air passage fro-m the interior of the bellows to the interior of the mask body, the passage being indicated in general by the numeral 142. A resilient flap valve 14-3 is anchored at 144 to an interior projection 145 in the arm 139 and extends diagonaly across the rectangular passage 142 normally closing the interior of the mask from the interior of the bellows. The end 145 of the flap valve 143 normally engage-s against a flange 146 partially closing the end of the passage 142. A sleeve 147 extends into the passage 143 through the wall of the arm 139 forming an air passage which is normally opened so that the interior of the mask can communicate with the outer atmosphere. Thus when the patient is exhaling or when the pressures on opposite sides of the flap valve 143 are equalized or are greater on the mask side of the valve the interior of the mask will communicate directly with the outer atmosphere. Men the bellows 168 are contracted, increasing the pressure Within the bellows, this pressure will force the flap valve 143 into engagement with the end of the sleeve, thus closing communication with the outer atmosphere. The end of the ilap valve will then bend downwardly sufiiciently to provide a communication from the passage 143 past the flap valve and into the interior or the mask. 7

In other words, the form of construction illustrated in FIGURES 12 through 14 of the drawings differs from the previous construction in shape and appearance and in the fact that the valve is in the mask supporting arm rather than built directly into the interior of the bellows. However, the operation of the device is quite similar to the constructions previously described. 7

One of the purposes of the arrangement illustrated in FIGURES 12 through 14 lies in the fact that the handle 113 is so shaped that it may be readily grasped between the thumb and fingers of one hand. At the same time, the other hand of the operator may be inserted over the mask between the arms 137 and 13? and the fingers may be used to hold the mask in place while the bellows is expanded and contracted by pulling and pushing on the handle end 113.

In accordance with the patent statutes, I have described the principles of construction and operation of my improvement in respiratory devices, and 'While I have endeavored to set forth the best embodiment thereof, I desire to have it understood that changes may be made within the scope of the following claims without departing from the spirit of my invention.

I claim:

1. A respiratory device including a bellows terminally connected to a pair of bellows ends, a respiratory mask connected to one of said bellows ends, a conduit extending from said mask through said one bellows end into said bellows, a valve chamber connected to said passage, said valve chamber including one passage leading to atmosphere, said valve chamber also having a second passage therethrough forming communication with the interior of said bellows, a valve operable to close said one passage to atmosphere and open said second passage, or to close said second passage and open said one passage to atmosphere, and a check valve admitting atmospheric air into said bellows upon expansion thereof and preventing the escape of air as said bellows is contracted, whereby, upon contraction of said bellows, air may be forced through said valve chamber and into said mask to induce positive pressure breathing, and upon expansion of said bellows air may be inhaled and exhaled from said mask through said valve chamber to said conduit to atmosphere, said valve in said valve chamber including a resilient flap valve secured at one end to. said valve chamber and having its opposite end free to flex between two extreme positions, said valve chamber fitting closely against the sides of said flap valve and against the free end thereof, said flap valve in one position normally closing one of said passages, said chamber including a shoulder which remains in close engagement with the end of said flap valve to maintain said second passage closed until the flap valve closes said one passage, further flexing of the 3. The structure of claim 1 and including a medicament receptacle in the conduit between said mask and said valve chamber, a medicament chamber in said receptacle, a by-pass passage through said receptacle, and a valve selectively operable to connect said mask to said valve chamber through said medicament chamber when said air is flowing toward said mask, or through said bypass when air is flowing from said mask.

4. The structure of claim 1 and including a housing connected to one bellows end and encircling said bellows, said housing being detachably connected to the other bellows end in contracted position of said bellows.

5. The structure of claim 1 and including a pressure relief valve on one of the bellows ends, and in which said pressure relief valve includes a whistle.

6. The structure of claim 1 and in which one of the bellows ends includes an inlet communicating with said check valve and a filter element detachably secured in said inlet.

7. A respiratory device including a bellows terminally connected to a pair of bellows ends, a respiratory mask connected to one of said bellows ends, a conduit extending from said mask through said one bellows and into said bellows, a valve chamber interposed in said passage, said valve chamber including one passage leading to atmosphere, said valve chamber also having a second passage therethrough forming communication with the interior of said bellows, a valve operable to close said one passage to atmosphere and open said second passage, or to close said second passage and open said one passage to atmosphere, and a check valve admitting atmospheric air into said bellows upon expansion thereof and prevent ing the escape of air as said bellows is contracted, whereby, upon contraction of said bellows, air may be forced through said valve chamber and into said mask to induce positive pressure breathing. and upon expansion of said bellows air may be inhaled and exhaled from said mask through said valve chamber to said conduit to atmosphere, said valve in said valve chamber comprising a flexible resilient flap valve normally closing said second i0 passage, said flap valve being secured at one end to said valve chamber and having its side edges in sealing engagement with said valve chamber, and a: shoulder in said chamber in sealing engagement with the end of said flap valve and maintaining said second passage closed until said one passage is closed, said flap valve being flexible into position to close said first passage and to open said second passage, the end of said flap valve remaining in sealing relation with said shoulder until said first passage is closed.

8. A respiratory device including a bellows, a pair of bellows ends attached to the ends of said bellows, a face mask connected to one of said bellows ends, a valve chamher, a conduit connecting said valve chamber to the interior of said mask, an air conduit extending from outer atmosphere and terminating in said valve chamber, a resilient flap valve secured in said valve chamber, said valve chamber having an opening therethrough communicating with the interior of said bellows which opening is normally closed by said flap valve, said conduits being normally connected through said valve chamber, said flap valve being movable into position to close said air conduct, walls in said valve chamber contacting the side and end edges of said flap valve in sealing relation therewith until said flap valve flexes into air conduit closing position, further flexing of said flap valve opening connection between said first named conduit and the interior of said bellows, and means operable for admitting air into said bellows upon expansion thereof.

References Cited in the file of this patent UNITED STATES PATENTS Re. 24,193 Emerson Aug. 7, 1956 2,362,643 Lambertsen Nov. 14, 1944 2,399,643 Kreiselman May 7, 1946 2,598,525 Fox May 27, 1952 FOREIGN PATENTS 533,297 Great Britain Feb. 11, 1941 799,225 Great Britain Aug. 6, 1958 

8. A RESPIRATORY DEVICE INCLUDING A BELLOWS, A PAIR OF BELLOWS ENDS ATTACHED TO THE ENDS OF SAID BELLOWS, A FACE MASK CONNECTED TO ONE OF SAID BELLOWS ENDS, A VALVE CHAMBER, A CONDUIT CONNECTING SAID VALVE CHAMBER TO THE INTERIOR OF SAID MASK, AN AIR CONDUIT EXTENDING FROM OUTER ATMOSPHERE AND TERMINATING IN SAID VALVE CHAMBER, A RESILIENT FLAP VALVE SECURED IN SAID VALVE CHAMBER, SAID VALVE MEMBER HAVING AN OPENING THERETHROUGH COMMUNICATING WITH THE INTERIOR OF SAID BELLOWS WHICH OPENING IS NORMALLY CLOSED BY SAID FLAP VALVE, SAID CONDUITS BEING NORMALLY CONNECTED THROUGH SAID VALVE CHAMBER, SAID FLAP VALVE BEING MOVABLE INTO POSITION TO CLOSE SAID AIR CONDUCT, WALLS IN SAID VALVE CHAMBER CONTACTING THE SIDE AND END EDGES OF SAID FLAP VALVE IN SEALING RELATION THEREWITH UNTIL SAID FLAP VALVE FLEXES INTO AIR CONDUIT CLOSING POSITION, FURTHER FLEXING OF SAID FLAP VALVE OPENING CONNECTION BETWEEN SAID FIRST NAMED CONDUIT AND THE INTERIOR OF SAID BELLOWS, AND MEANS OPERABLE FOR ADMITTING AIR INTO SAID BELLOWS UPON EXPANSION THEREOF. 